JPS6142164B2 - - Google Patents

Description

Detailed Description of the Invention This invention automatically performs an operation to stabilize combustion when a combustion abnormality occurs, and when the combustor itself cannot recover from an abnormal state to a normal state, the combustion It is intended to stop.

Conventionally, for the same purpose as the present invention, there has been proposed a combustor that constantly detects the flame current during combustion and continuously controls the amount of combustion air so that the flame current reaches a set value. However, although the above configuration is theoretically possible, the actual flame current constantly fluctuates due to flickering of the flame, noise, etc., and it is extremely difficult to synchronize it with the amount of combustion air. In an actual combustor, the output of the flame detector is taken out as an output of flame presence or no flame through a time constant circuit made up of a capacitor and a resistor, and when no flame continues for a certain period of time, it is determined that combustion cannot continue, and the combustor It is intended to stop. Therefore, when a signal indicating no flame is output, the flame current is often flowing even though it is decreasing, and although it is abnormal, it is considered that combustion is occurring. If an operation is performed to normalize the abnormal combustion during this time, a flame signal will be generated again, and the worst situation for the operator, which would be an emergency stop of the combustor, cannot occur.

This invention provides that the cause of the abnormal combustion state, which is a decrease in flame current, is caused by a lack of internal combustion air, and that the operator can treat it as a result of a clogged filter or indoor air contamination due to poor ventilation. It was developed with the focus on the fact that most of the parts can be easily repaired through normal handling operations, and an alternating current voltage is applied between the burner 1 and the flame rod 2 inserted into the burner flame, causing the flame to ignite. In a combustor that detects the combustion state by rectification and stops combustion when the flame current decreases, the combustion air amount increasing means 3 is activated when the flame current decreases, and combustion is started when no increase in flame current is recognized. This relates to a combustion control device that stops.

A PTC heater 4 is attached to the bottom of the burner 1, combustion air is supplied to the burner 1 by a blower 5, and a flow rate controller 7 is attached to the air pipe 6. 8 is an oil level regulator, in which the pressure of the air pipe 6 between the flow rate controller 7 and the burner 1 is applied to the oil level regulator 8 through a pipe 9, and the pressure of the pressurized oil level regulator 8 is Oil is sent to the burner 1 by a fuel pipe 10. Therefore, by operating the flow rate controller 7, the combustion air amount and the twisting material flow rate can be controlled together. 11 is fuel pipe 1
12, which is the electric fuel valve 0, is a bypass pipe that directly supplies air from the blower 5 to the burner 1, and a combustion air amount increasing means 3 is installed in the middle, and the air amount increasing means 3 is sucked by a solenoid 13 when activated. On-off valve 14
is opened and air is supplied to the burner 1 from the bypass pipe 11. 15 is a convection fan, which starts when the combustor reaches a certain temperature and stops when it cools down.

When the operation switch is closed during use,
When the PTC heater 4 is energized and the burner 1 reaches the vaporization temperature, the preheating lamp lights up. Then, when you press the start switch, relay X1 is activated and blower 5
rotates and supplies combustion air to burner 1. about 10
After a few seconds have elapsed, relay X2 operates to energize igniter 16 and solenoid valve 11. For this purpose, fuel is sent from the oil level regulator 8 to the burner 1, and the vaporized fuel and air form a mixed gas. When ignition combustion is started by the igniter 16, a flame current flows through the flame rod 2, and the igniter 16 stops operating after a certain period of time.

If a flame current of a certain strength does not flow even after approximately 20 seconds have passed after operating the operation switch, the output 17 of the flame detector remains unchanged, relays X1 and X2 are opened, the blower 5 is stopped, and the solenoid valve 11 is closed. Closed. On the other hand, if a flame current of a certain strength can be detected within about 20 seconds, the output 17 of the flame detector will be set and combustion will continue. Further, to stop combustion, if the operation switch is opened, the PTC heater 4, blower 5, and solenoid valve 11 are de-energized and combustion is stopped instantly.

When the combustion condition deteriorates and the flame current decreases, the output 17 of the flame detector becomes low and the 20 second timer starts operating. On the other hand, during normal combustion, a transistor that is in a conductive state maintains a conductive state for a short time even when the output 17 of the flame detector becomes low due to the function of a capacitor, and transistors connected in series maintain a conductive state for a short time even when the output 17 of the flame detector becomes low. Since it becomes conductive for the first time when the diode cools down, the diode operates the self-holding circuit of relay X3. For this reason, the relou X3 absorbs the solenoid 13 and supplies combustion air to the burner 1 from the bypass pipe 12.

If the deterioration of the combustion state is caused by a lack of combustion air, if combustion air is supplied from the bypass pipe 12, the combustion state becomes normal and the flame current increases. When this flame current does not increase after about 20 seconds, that is, when the cause is due to the fuel supply, relays X1, X2, and X3 become non-conductive and combustion stops.

It is effective to provide some means of checking when the combustion air amount increasing means 3 is activated and combustion is normal, and if the operator cleans the air filter or ventilates the air, the amount of combustion air will increase from the next use. Means 3 becomes inoperative. If the combustion air amount increasing means 3 operates again during the next use, the cause is considered to be the combustor, and a repair request procedure can be taken.
In the embodiment, when the combustion air amount increasing means 3 is activated, the air amount lamp lights up to indicate to the operator the necessity of cleaning the air filter and ventilation, and when the operator presses the return button after maintenance inspection, the cause is corrected. If the air filter is clogged, the air quantity lamp will not light up again.

As described above, since the present invention has a means for increasing the amount of combustion air that causes the combustor itself to return to normal combustion in the case of abnormal combustion due to lack of air, the range of use of the combustor is increased, and even with the means for increasing the amount of combustion air. In the case of a serious problem where the lack of air volume cannot be resolved, combustion will stop immediately, so safety is extremely high.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of this invention, and FIG. 2 is a circuit diagram of the same. 1...burner, 2...flame rod, 3...
Means for increasing the amount of combustion air.

Claims (1)

[Claims] 1. In the combustor, an AC voltage is applied between the burner and a flame rod inserted into the burner flame, the combustion state is detected by the flame rectification effect, and combustion is stopped when the flame current decreases. A combustion control device that operates a combustion air amount increasing means when the amount of combustion air decreases and stops combustion when an increase in flame current is not recognized.